1. Field of the Invention
This invention relates to power devices. Specifically, the present invention relates to semiconductor power devices.
2. Description of the Related Art
Techniques have been developed for producing W-band semiconductor power devices (e.g. 50 Ghz to 120 Ghz). For example Gunn and Impatt diode sources have been developed which produce xc2xc watt of power. However, these sources are very expensive. Indium Phosphide High Electron Mobility Transistor (InP HEMT) amplifiers have been developed which produce {fraction (1/10)} watt of power. However these devices range from $10,000 to $20,000 in cost. Lastly, technologies are being developed which produce heat with high-frequency microwave beams. These technologies require power in the 100 KW to 1 MV range. However, devices implemented with these technologies (tubes) may cost millions of dollars each.
In general, devices implemented with conventional technologies do not generate affordable power in the W-band. In addition, the flexibility of conventional power systems, such as Gunn and Impatt diodes and InP HEMT amplifiers, is limited.
Thus, there is a need in the art for a cost effective high power W-band power system. That is, there is a need in the art for a W-band power system that can be inexpensively configured, to provide variable output power levels. Lastly, there is a need for a W-band power system that takes advantage of current semiconductor manufacturing technology to minimize costs.
The need in the art is addressed by the reflector of the present invention. Generally, the inventive reflector includes a monolithic semiconductor substrate and a mechanism disposed on the substrate for coherently reflecting electromagnetic energy.
In the illustrative embodiment, the mechanism is a monolithic array of cells with each cell including transmit and receive antenna and an amplifier therebetween. In the best mode, the antenna is a dual polarization antenna. That is, the receive antenna receives incident electromagnetic energy with a first polarization. This energy is amplified and provided to the second antenna, which retransmits the energy at an orthogonal polarization. The combined output of the cells is a coherent electromagnetic wavefront.